Apparatus for mixing material for making roads



July 19, 1932. w. G. FRAZEE APPARATUS FOR HIKING IATERIAL FOR MAKINGROADS eet s-Sheat 1 Filbd Sept. 25 1929 Jaa' July 19, 1932. w. s. FRAZEEAPPARATUS FOR MIXING MATERIAL FOR MAKING ROADS Filod Sept. 25, 1929 13Sheets-Sheet 2 NAN v maxi y 1932- w. G. FRAZEE 1,867,739

APPARATUS FOR MIXING MATERIAL FOR MAKING ROADS Filed Sept. 25, 1929 13Sheets-Sheet 3 July 19, 1932. w, G. FRAzgE 1,867,739

APPARA TUS FOR HIXiNGMATERIAL FOR IAKING ROADS Filed Sept. 25, 1929 13Sheets-Sheet 4' July 19, 1932. w. G. FRAZEE APPARATUS FOR MIXINGMATERIAL FOR MAKING ROADS 13 Sheets-Sheet 5 Filed Sept. 25, 1929 July19, 1932.- we. FRAZEE 1,867,739

APBARATUS FOR MIXING MATERIAL FOR MAKING ROADS Filed Sept. 25 1929 13Sheets-Sheet e Int/c04 0? July 19, 1932. n w. s. FRAZEE 1,867,739

APPARATUS FOR MIXING MATERIAL FOR KING ROADS Filed Sept. 25, 1929 13Sheets-Sheet '7 y 19, 1932- w. G. FRAZEE' 1,867,739

APPARATUS FOR MIXING MATERIAL FOR MAKING ROADS Filed Sept. 25. 192913-5heets-Sheet s July 19, 1932. w. G. FRAZEE 1 ,867,739

APPARATUS FOR I IXIAIG IATERIAL FOR IAKING ROADS Filed s it. 25, 1929 13Sheets-Sheet 9 July 19, 1932. w. s. FRAZEE APPARATUS FOR IIXING IATERIALFOR IAKING ROADS 13'Sheets-Sheet 10 Filed se i. 25 1929 y 1932- w. G.FRAZEE 1,867,739

APPARATUS FOR MIXING MATERIAL FOR MAKING ROADS Filed Sept. 25, 1929 13Sheets-Sheet 11 y 19, 1932- w. G. FRAZEE 1,867,739

I APPARATUS -FOR MIXING MATERIAL FOR MAKING ROADS Filed Sept. 25, 19291:5 Shasta-Sheet 12 Walk 2 5/1665 4 July 19, 1932. w. G. FRAZEE1,867,739

APPARATUS FOR MIXING MATERIAL FOR MAKING ROADS Filed Sept. 25, 1929 13Sheets-Sheet 13 Patented July 19, 1932 I PATENT/W 'RE- WALTER GUYFRAZEE, orcn'nau' :mins'iowa, tenants rd iowa immmmm COMPANY, or CEDARmrzns, rowa, A..coR1=oRa'm;oivor rowA.

ARA S roe M x s u mains w Application filed se tem'b ras, 1529, SerialNo. 395,026.

My invention relates to ansapparatus signed to be employed in connectionthe construction of highways for :forming a.- ravel or crushed stone andan asphaltic binder-tot the usually termed road oil,-wh1ch 1s relativelycementitious mixture of heavy and viscous at ordinary atmospherictemperatures, but thin and tree fiowing'when a heated. In theconstruction of such grave]; or crushed stone roads surfaced with-1acemented mixture :of the gravel ia'ndj road 2 oil-- it is commonpractice to spraythe oil in: heated and fluid condition upon thetop of?the gravel, and then plow the surface toiiiix the oil and gravel, thespraying and'plowing being frequently repeated; and the suriace-*finally rolled to compact This procedure is entirely impossiblethroughout the w nter season in the cooler climate, and-even in thesummer time, ifthe gravel is at all damp good results are impossible;-Furthermore, even under the most favorable atmospheric'and climaticconditions t'he h'eated .oil cools. more; or less irregularly whilebeing applierhso that uniformly-good results cannot be :oh-' tained. Theobject of my inventlonis the. provision of an efficient apparatuswhich'v shall be free from the objections incident to the prior practicementioned, andwhich to.

that end, shall employ means for drying and heating the gravel andmixing it with the proper amount of heated oil at or near the section ofthe road being surfaced, continuously and in manner and quantitysufficient to be applied in mixed and heated condition: to the roadway,and which can readily be. moved as the work of road making progresses toenable the construction of the road to be carried on conveniently andrapidly, andunder relatively unfavorable climatic conditions.

In carrying out this main purpose and ob-' I have devised and inventedthe road material mixing apparatus illustrated in the accompanyingdrawings and hereinafter described in detail and embodying various novelfeatures in the combination and arrangement of parts of the apparatus incooperative relation to effect the results and accomplish the ends inview; in the provision ofrmeans "for causing a substantially continuousand regulated how of raw .materials through the drying and heating andmixing devices to the mixed material compartmentof the 'apparatusyin thearrangement of the'fraine Work and various portions oftheiapparatu's'inseparable parts and units to permiti convenient transportation of theapparatus; antlin various improvements and novel details of constructionrelating'to certain portions or the apparatus, as the dryingdrum,agravel and oil feedingmeans, hoisting devices, etc.,incidentalitoitliefeatures of construtgtiofibefotementiohdw Inztheappended claims. the essential ele-' mnt sof my invention are moreparticularly pointed 301117, it being understood, however, that myinvention is susceptible of variation and modification in theconstruction and arrangement'ofjvarious" parts, and by the sub"stitution ofcquivalentmeans and mechanism for those particularlydescribed; and I: there fore intend' th'at' my'claims shall be construedto include all such modifications and equivalent elements, sofar as they"fall within the true spirit a'nd scope of my invention'and' are notfound 'inthe'prior art. 1

' Of the drawings 'which illustrate a road material mixing apparatusembodying my invention in a desirable and preferred form;

Figure 1 1s an elevation of what willbe termed the right-side of theapparatus, set up and connected for use;

Fig; 2is a plan view of the same;

Fig; 3 is an end view of theapparatus looking from what will arbitrarilybe termed the rzlad end of the apparatus towards the front 911 l Fig. 4is avertical section of the heating drum in 'a' plane extending axiallyof the same;

Figs. 5 and 6 are cross-sections of the same on planes indicatedrespectively by the dotted lines 5-5 and 66, viewed in the directionindicated by the arrows;

Fig. 7 is a view looking from rear to front of the end of the combustionchamber casing and the discharge chute of the drying drum;

Fig. 8 is a side view of a reciprocatory feeder for regulating thepassage of gravel valves for shutting off sections of thecoil at will;

Fig. 10 is a vertical section of a pug m1ll,

showing also certain mechanisms regulating the-supplyof materials to it;

feeder illustrated in.Fig..8; I

Fig. 11 is a'detail of construction ofthe feeder supporting frame; 7Fig. 12 is a view of one of four similar ratchet mechanisms used forraising and lowering .thetwo compartment bin structures used to ?containthe raw gravel and. mixed materials --Fig. 13 isa transversesection ofthe elevatoricasing. on the dotted line 13-13 of Fig. l;

.7 Fig; 514 is-an elevation of thesleft side' of thel1'eatin-g;-drum-1and asupportingv truck and other parts of theapparatus carried by.

said truck; 3

Fig; 151s an elevation of the in Fig. 12 viewed atrig'ht angles -to;theposi tion-shownin. such figure; 1 w Fig. 16 is a detail showing in topplan view certain slide members or shoes used for connecting'one of thecorner posts and the adjacent=corner of the bin structure;

tending longitudinally of; the machine, of a measuring device fordelivering. heated grav-'-.

el tothe pug .mill; 2'.

Like reference characters indicated like parts in all the figures of thedrawings.

Before entering upon a detailed description of the construction of theapparatus, its generalorganization may first be briefly explained. Theapparatus, or material mixing plant includes a framework of knock-downconstruction made up of corner columns or posts and bracing andconnecting members 7 I material mixed with road oil. Fig. 11 is an endviewof the reciprocating gravel and road oil and the motor for operatingthe pug-mill together with gravel and oilmcterin or measuring devicesand certain registerlng' instruments. associated with the ug-mill andcertain connecting parts and members. The .bin structure forms oneseparable unit which in the completed structure ready for operation is.se-- curedrto the corner-columns, and-the pugmill platform and partscarried by. :itform a'second separable. unit,--also secured to thecorner supportsfiand b'oth units -are,soconstructedthatthey may beloaded together on a truck for transportationwhen the apparatus is to'be moved to a different location-- The remaining. portions of theapparatus are in the present instance all carried by a separate singletruck by which they may be 4 transported from' one location to another..-.F ig'.17 is a detail showing in side elevationcertain, adjustingmechanism at the lower. end of theichain of elevator buckets; -ig., 18.is faverticalsection, :in-.-a plane. ex-- These portions include arotary drying and heating cylinder or-drum arranged to receive,the:-:raw gravel, a-burner for-heating the-drum, an elevator fortransferring the dried and heated gravel to the. pug-mill on theframework before mentioned, apump arranged to be connected with a-supplyof roadv 1.,Fig 19 isa view, looking towards theleft. side ofthemachine, of the automatic weight-v oil and operatingto force the oilthrough a heating coil associated with the heatin drum beforementioned'an'd through a meterlngdevice which delivers it to thepug-mill, and a motor and connections for rotating the heating drum andactuating the feedingdevice ing plate 3 and at their lower ends arebolted to said corner posts. The other two corner po'sts 14 at the leftside, are similarly connected together by diagonal bars marked 2 and allfour of the corner posts, which are formed of I-beam structural iron,are

equipped each at their lower end with a supporting base structure 7 ofsuitable construction to provide adequate support on the ground.

The upper portions of the posts are connected together by the separableplatform unit which includes a pair of beams 6 6 extending from front torear of the. apparatus and a pair of cross beams 77 resting upon lieadjacent the outer ends of suchbeams in the four outer angles which thebeams make with each other at the corners of the frame. The beams 77 arealso connected by frame bars 8, 9, 10, 11, l2and 13, to provide aplatform frame to which are rigidly secured grating sections marked 14,15, 16, 17 and 18 which form a walkway. Around the outside of the groupof gratings forming the walkway is arranged a railing which may beconstructed of supporting members 19 and railing members 20, 20 securedto the platform frame and arranged as illustrated or in any othersuitable manner.

For the purpose of affording access to' the pug-mill and other parts ofthe machine reached by the walkway above mentioned, I

have provided a stairway marked 121 as a whole, extending from theground to the platform frame and arranged to-land adjacent the gratingsections 16 and 18 at the left hand front portion of the framework.

The two-compartment bin unit for holding the raw gravel and the heatedtreated mixture is a rectangular structure which includes four verticalleg members 22 at its corners which may conveniently be formed of angleiron, and connecting frame members 23 tc which are riveted sheet metalplates 24 forming the upper walls of the bins and a cross partition 25separating the bins. The four inclined and converging bottom walls 26'of each bin are similarly construetedvgf sheet metal walls riveted tosuitable frame members and terminate indischarge Openings at the bottom.I

The two legs members 22 of the bin unit at each side of the machine areconnected near their bottom *ends by a cross bar 27, and the legsandframe work preferably are braced by diagonal and vertical bracingmembers, all

marked 28, directly riveted together, or connected through connectingplates, as the plates marked 29.

At'the four corners of the bin strueure the angle-iron leg members 22are equipped with pairs of shoes or slides 3O30 adjacent their top andbottom ends which extend over the flanges of the leg columns and serveas guides in raising and lowering the bins when setting .up theapparatus. Each slide 30 extends over the portion of the'flange on oneside of the particular I-beam extending from the central web in onedirection and the corresponding slide 30 extends over the oppositeportion of said flange.

Both the pug-mill platform and the bins,

temporarily bolted together for the purpose, are raised and lowered uponthe corner columns by means of a special hoisting mechanism which I havedevised for the purpose, the actuating parts of one member of which areshown in detail inFig. 12. This apparatus (see Figs. 12, 15, 18 and 19)includes four cables 31 arranged to run over winding drum 32 severallyrotatably mounted in bearings carried by the supporting bases 7 of thefour corner posts, and each engaging in turn a sheave 33rotatablymounted in a bracket 34 at the top of the particular cornerpost, a sheave 35 carried by the base of the pug-mill platform, and asheave 33 which is mounted on the same pivot pin as the sheave 33, theends of the cable being anchored to the corner post adjacent the sheave35.

As shown in Figs. 12 and 15, each winding drum 32 is associated witharatchet wheel 36 which is fixed to the short shaft, marked 37 to whichthe drum 32 is itself secured. This sh aft 37 may conveniently bemounted. as shown, in a pair of bracket plates 38 riveted severally tothe vertical flanges of a pair of blocks 39 which are L-shaped incross-sec tion and which are riveted to the opposite 39, and isyieldingly stressed into engagement with the ratchet wheel 36 by acoiled compression spring 43. The pawl 44 of the mechanism is pivoted toa rocking actuating lever 45 which itself is pivotally mounted in thebearing block 42 before mentioned and is formed with an extension 450below the pivot forming a blocking member. As shown, the pawl 44 isformed with a tail 440 which at times cooperates with the lower end of aspring-pressed trigger 46 slidably mounted in the body member 45 of theactuating lever. This trigger is formed with a right angled bend at itsupper end which may be latched in a notch 451 in the upper end of thebody member 45 to hold the trigger in inoperative usual manner.- Whenlowering the bins and platform (assuming the parts to be in the positionshown in Fig. 12-), the foot treadle is first depressed and held down todisengage the detent 41, and the handle then lowered under the load ofthe parts connected to the cable, in the course of which movement thepawl 44 will assume a more nearly horizontal position, and its tailportion 440 will contact with the trigger 46 and shift it, compressingits spring. The foot lever is then released to permit the detent 41 toengage a ratchet tooth, and as soon as the stress on the pawl 44 isrelieved the spring-pressed trigger 46 will snap it out of engagementwith they tooth of the ratchet wheel, when the operating handle may belifted to make a new engagement between the pawl and ratchet wheel, andthe operation repeated.

It may here be explained that in setting up the apparatus the cornerposts or columns are connected separately to the four corners of the binby means of the slides 3030 before mentioned, while the bin and pug-millplatform (which at the time are temporarily bolted together at eachcorner) in the lowered position required for transportation, and theplatform (carrying with it the bin structure), is then hoisted to aposition in which the proper level and the bin legs bolted to the cornerposts or then securely columns. To

secure adequate strength and rigidity the corner legs of the bins are inthe present instance bolted to the corner post at their top and bottom,and also at an intermediate point. The braces 2 -2 and 2-2 are thenbolted. to the corner posts and to the crossbars 27 of the bin frame tofurther secure rigidity, and the pug-mill frame is then unbolted fromthe bins and raised further to its proper position and bolted to thecorner posts.

Passage of material through the discharge opening at the bottom of thebin (marked A) for containing the cold raw gravel is controlled by afeeding mechanism which may be adjusted to deliver a regulated supply ofmaterial to the heating drum later to be described. This mechanism (seeFigs.v 1, 8 and 11) is detachable from the bin structure for purposes oftransportation, and consists of a detachable framework, marked 50 as awhole, suitably constructed to be bolted to the framework of the binunit above described, in which is mounted a reciprocating feedingmechanism having a variable throw. The feeder frame-includes a pair ofbeams 501-502 arranged to be bolted at their right ends to the cross-bar27 of the bin frame, and at their opposite ends arranged to be similarlybolted to a cross-bar 503 secured to the lower ends of vertical bars 508secured to the bin frame. To the beam 501 is secured bin structure willstand at-its-l 504 being connected by other frame members 505 runningfrom front -torear and crossmembers 505 to form a skeleton boxstructure.

Within the skeleton box structure and stationarily supported by pairs ofvertical bracket members 51-51 secured to the opposite frame bars505-505, (see Fig. 8) is a feeder box having a front wall 506, sidewalls 507, a collar 508 surrounding the neck 509 at the bottom of thehopper, and a top wall 510 to the rear of the collar 508,see Figs. 8 and11. The rear end of the feeder box is open and immediately below theplane of the lower edges of the side walls and front Wall is arranged. areciprocating feeder plate 54 formed-with opposite side flanges 540which extend upwardly along the side walls of the feeder box.Immediately below the plane of the bottom of the collar 508 and also ofthe neck of the hopper,'is arranged a sliding gate 511 which may bemanually operated in any suitable manner, as by means of a handlever512.

The feeder plate 54 before mentioned is supported by pairs of oppositerollers 55 journaled in. the lower feeder frame members 505, and isreciprocated by a rocking frame consisting of a rock shaft 58 to whichis secured a central vertical rock arm 56 equipped with a rollerarranged to work between a pair of blocks secured to the under side ofthe plate 54 centrally thereof, and

including a horizontal arm 57 secured to said shaft at one side of theframe, this arm preferably being telescopic in construction, asshown,for the 'purpose of adjusting its length. The is pivoted inbearings 59 carried by opposite bearing brackets 59 secured to the lowermembers 505 of the feeder frame.

The discharge opening at the bottomof the bin (marked B) for containingthe heated mixed material is arranged to be opened and closed by meansof a manually operated gate or slide 60, (see Fig. 3).

The pug-mill which forms a part of my .material-mixing apparatus may beof any suitable design, the general construction employed by me beingillustrated in Figs. 2 and 10, from which it will be noted that the millincludes a caslng 61 mounted upon base members 62 and having end' wallsin which is rotatably mounted the shaft 63 to which sectional hubsections carrying spaced blades 64 are secured to form a strong andrugged mixing and stirring member. The motor 65 for driving the pug-milland the clutch 66, both of which are shown diagrammatically, may be ofany suitable construction adapted to perform the well understoodfunctions of such devices, numerous commercial forms being well known. Aworm-driven reducing shaft '58 of the rocking frame gear device 67connected to the driven clutch member of the clutch 66 is also showndiagrammatically, and as the purpose and con:- struction of such devicesare well known no detailed description is considered necessary. To theend of the shaft carrying the worm Wheel of the reducing gear is fixed asprock et whee-l connected by a sprocket chain 69 with a sprocket Wheel70 fixed to the end of the shaft 63 of the pug-mill. A. gravel measuringdevice for delivering measured charges of heated gravel to the pug-mill,and a metering device for simultaneously delivering measured charges ofheated road oil to said mill, both mounted on the pug millplatform, willbe described at a later point.

Turning now to a description of the parts permanently mounted upon atruck for transportation, (see Figs. 1, 2, 3 and 14) the frame of thetruck is, in the assembled-apparatus when ready for operation, arrangedat the right side,-irnmediately to the rear of the raw material bin A.The'longitudinal side beams or sills 71 of the truckframes are connectedby angle plates, orother'wise, with; cross beams 72, 72, 72", 73, 74,75, 76, 77,78and 79 to form a rigid frame which is'supported on thefront wheels18080 and rear wheels 8l--81,,the non-rotatable axle of thefront wheels being pivoted to rock upon abolster block 82 in order thatthe wheels may adjust themselves to irregularity in'the surface of theground. I The drying and heating cylinder or drum 83 is-equipped nearits rear end with a hear? ing ring 84,- and at a point between itscenterand front end with a similar bearingring 85, through which it isrotatabiy-su'pported upon a pair of front bearing rollers 86, anda pairof rear bearing rollers 87. The front rollers are flanged at their rearside'sand are jour naled in bearings carried by the cross-beams 72 72",and the rear rollers are flanged on the front sides and are carried bythe cross beams 7 57 6 (see Figs. 1, 4 and 14) It will be understoodthat the two rollers" 86 are arranged to engage the ring 85 on oppositesides of the vertical axial plane of the cylinder, and that the rollers87 are similarly arranged. The flanges of the rollers 86 and 87 serve toprevent longitudinal displacement of the heating drum, but to relievethe rearward strain upon the roller 86 I have provided a thrust bearingarranged vertically beneath the axis of the drum.

As illustrated (see F ig. 4) this thrust bearing comprises a roller 88rotatably mounted on an approximately vertical axis in a block 89 whichis adjustable in a forward and rearward direction on a seat formed bythe top faces of the cross-beams 7272 by means of an adjusting bolt 90engaging a threaded seat in a lug formed on the lower side of the block89 between the two cross beams.

At its front end the heating cylinder or drum is surrounded by astationary hood 91, the annular front wall 92 of which makes sealedconnection with the cylinder between the outwardly projecting flanges oftwo. sectional rings 94.94" which are clamped tightl to the drum.-against an interposed asbestos gasket-93 by u'ieinis of clamping lugs atthe meeting ends of the sections of the-rin gs. It will be noted thatthe distance between the sealing rings 94 the front-thrust roller 88 issmall, which hasthe advantage of minimizing trouble which ngight arisefrom =expa-nsion' of the drying drum.

To the top portion of this head is secured the base portion lfle of thesmoke stack 106, which is hinged to the baseportion, so that it may beturned to a horizontal position for transportation, as indicated ,bydotted-lines in Fig. 1. At the bottom of the front wall of the hood andopening into adownwa-rdly olfset portion thereof, Ihave provided ahinged door 91 (see Figs. 4.420 11) ,to;enable the dirt and soot whichmay collect in the hood to be cleaned out. 1

To the rear wall 95 of thehood 91 is se cured a hopper 96 extendingunder the dis charge end of the feed box and feeder plate 54 of thegravel feeding, mechanism beforede scribed, see Figs. 4 and 8, and atthe entrance of the hopper easing into the hood the opening isautomatically: variably opened and closed by a swinging gateorvalve 97which permits the stream of gravel to pass under it while closing theopening thereabove so as to prevent escape of the heated gases from thecylinder and maintain a good draft'inthe flue. The lower end of-thehopper extends into a large central opening in the annular front w-all98 of the drying and heating drum 83 and delivers the gravel in thepath-of a series of intake blades'99, the frontends of which are formedwith flanges bolted to the wall 98. Rearwardly of the blades 99, thedrum is provided with a series of inwardly extending L-shaped blades ortroughs 100 of the same number as theintake blades, and in the presentinstance arranged in longitudinal alignment with such blades, the troughmembers 100 having radial portions 101 secured by angle plates 102 tothe drum wall, and terminal flange portions 103. The rear end of eachintake blade extends spirally to and is secured to the leading face ofthe radial portion 101 of the trough member which is angularly behind itwith reference to-the direction of rotation of the drum, the inclinedarrangement of the intake blades acting to force the materialrearwardly'of the drum into the spaces between the trough members. Thesetrough inembers,.it may here be noted, terminate a shortdi'stanceforwardl of the rear end ofthe drying drum. 7 Y

It is obvious that as the raw gravel is worked from the higher front endof the drying drum towards the rear end, the material will be carried upby the troughson the ascending side and fall out as it 'passes' aroundthe top and that the dropping ofj the material through the heated streamof burning gases passing through the drum will effectively and quicklydry and heat every particle of it; The lower rear end of the dryingdrum'is surroundedby a stationary hoodor casing member 107,-see Figs. 3,ls-and -7,''the joint between the drums and easing being close fitting,or if- .desired, packed, to prevent escape of burning ases. "Immediatelybeneaththe rear end of the drying drum, a discharge chute 108 isremova-bly secured to the casing 107-, this chute being formed wit-ha.partition 109 separating a by-pa'ss passageway which is normally closeda swinging gate 110 equipped with a'weight 111 for thepurpose, and alower passage which is variably opened and closed by a swinging gate112' which yields to theweight of material pressing against it to permitpassage of the material therethrough. It'may here'be'explained that forthe purpose of ascertaining thete'mpera ture of the material passing-outof the drum the thermometer bulb '113'=of' arr-indicating thermometer113 is arranged in the by-pass, and when it is desired to make anobservation the-weight 111 is lifted to permit material to pass throughthe upper passage of the chute, and cause the temperature of the matrialto be indicated. Indicating thermometers of the 'type-employed by me,"asthewell known Foxboro indicating thermometers are well known in the art,and need not-be de: scribed in'detail. v

1 Extending through and secured to the rear wall of the hood 107 isarranged a cylindrical casing 114, lined with fire brick 115 enclosinghe combustion chamber of the apparatus. The heating means employed forheating-the drying drum may be a commercial oil burner of suitable type,as indicatedgenerally by the reference number 116, having a burner tube117 extending into thecombustion chamber. For the purpose oftransferring the dried and heated gravel delivered from the dischargechute of the drying drum to thepugrmill, I employ a separable elevatorincluding a lower frame section 118 to which hinged an upper framesection 119, the lower section being arranged to be detacbably securednear its lower end to a frame bracket 160 extending laterally fromtheright s ll 71 of the truck frame and supported in inclined position byan inclined bracing frame or strut 120. This bracing frame is pivotallysecured at its lower end to another frame bracket 161, also extendinglaterally from the right sill? 1 of the truck frame before mentioned.When the apparatus is taken down for transportation',"the brackets 160and 161 serve as-supports for the bracing-frame and elevaton'sections;"The frame section-1=18 of the elevator con- 123 mountedupon pivot pins124 secured to the bars, see Fig- 13; Each pin 124 is held in place by"set screw collars 162 equipped with set-screws 1631 Between the twocollars are interposed apair of tubular spacing blocks 16%164earrangedon opp-osite'sldes of a roller 123 rotatably mounted in the pivot pin,and for the purpose" of lubricating the bearing of the roller the-pin isprovided with a lubricating passage and: an alemite connection. Theframe section'119-is constructs ed similarlyto the section 118. 'Theelevator buckets '125-"are' secured to "pairs of links pivoted-to other'links at intervals by means-of pivot-pin's-126 to form a connectedehainor line 'of'buckets which ride over? the 115119125 1235 L: 1:

1 The frame se'etionsfi'are preferably provided, as sh0wn,""-:see Figs-2, 3 and 13,- with steps 2()O which may be of skeietonconstruction,rivetedI to the rightframe bars 0f the elevator. secfiqnsl; v illit. 1 41:1.

At=the lower nd- -of' the lower frame section,*for'the purpose'of takingup slack in the chain, due towea'r or other causes,- the frame bars (seeFig." 17 )-'are equipped with a pair i of bearing 'blocks' 167longitudinally adjustable by means-of adj ustingr -screws 168 upon framesections 127 secured to the bars 118; Between these bearing blocks ismounted an idler sprocket'wheel128 engaged by the pivots ofthe'el'evatorbucket linei The upper end "of the elevator frame section119' is detachably secured to the pugmill frame by means of a supportingframe 168 arranged to be bolted at its top and bottom to a pair ofbearing brackets 119 secured to-the side bars of said frame section andthe pug-mill frame respective1y,-see Figs. 1, 18 and 19. J ournale'dinbearings at the top of the two bearing brackets 119 is a shaft 170 towhich is "fixed a sprocket wheel 129arranged to engage "the pivot pinsconnecting the links of'the elevator bucket line." To the left end ofthis shaft 17 0 is fixed a gear wheel 136 which meshes witha gear wheel135 fixed to theleft endof a shaft 134 also journaled in'bearings on thetwo frame brackets 119. The-right'end of this'shaft 134 is arranged tobe connected and disconnected by means of a clutch 171 with a sprocketwheel 133 by means of which the gearing'wheels just described andelevator chain are driven (see Figs. 2, 3, and 19-). To this end theright end of the shaft of the pug-mill (which is driven inthe'manneralready described) is equipped with a sprocket wheel 131which-is engaged by a sprocket chain 132 arranged to drive thesprocket'wheel 133 and connected chain of elevatonbuckets. v The movable-member of the clutch 171 is in measuring drum having the presentinstance arranged to be shifted by means of an operating rod 172extending from the clutch member to the left to aconvenient osition forits bent end to be grasped y an operator upon the pug-mill platform,through a housing member 173 secured to the elevator frame structure andshielding the gear wheels 135 and 136,-see Fig. 3. The u er loop of theelevator bucket line is covere by a hood 130 extending from the top ofthe upper cover piece 122 of the elevator to the casing of a measuringdevice next to be described; For the urpose of observation the hood 130is preferably provided with a door 130, as illustrated.

It will be noted that the elevator bucket line is completely enclosedand shielded from a point adjacent the delivery chute at the end of theheating drum to the point of delivery of the dried and heated materialto the pugmill, whereby any considerable cooling of the material isavoided.

The dried and heated gravel discharged "from the elevator buckets withinthe hood 'This device includes a casing having at the.

top guide plates-174175 which direct the gravel from the buckets to thecenter of a semi-cylindrical chamber 176 of the casing in which isarranged to work an oscillating arallel circular sides and three radialbla es, marked 177, 178 and 179. The blade 177 is arranged to oscillatefreely within the semi-circular wall of the chamber 176, but the blades178 and 179 are of such length as to severally bring up, in extremeopposite positions of the drum, against the shoulders which thesemi-circular wallof the chamber 176 makes with portions of the top wallof a rectangular discharge chamber therebelow, see Fig. 18. The

shaft 180 on which the drum is mounted is counterweighted outside thecasing (see Figs.

:19 and 20) by a weight 181 adiustably seto receive gravel from theelevator buckets,

while in the opposite position the blade 179 will form the floor of asimilar compartment between it and the blade 17 7. It is obvious thatwhen the gravel in one compartment accumulates to a given weight it willovercome. the counterbalancing effect of the weight and discharge thematerial through the discharge passage into the pug-mill, reversing theposition of the weight and drum in doing so, andthat the material willthen accumulate in the other chamber with a like result, the

heated gravel being-thus discharged into the mill in-regular measuredcharges. The size of the charges may be regulated by adjustment of theweight 181 on its lever.

The rocking of the measuring drum and counterweight serves also to bringabout the discharge of measured charges of heated road oil into thepug-mill through a meter ingdevice. This device (see Figs. 20 and 21)includes a cylinder 183 formed with a central partition 184, and adouble piston having heads 185 and 186 which work in said cylinder onopposite'sides of said head, the heads being suitably packed, and thepartition being packed around the piston stem 185, as illustrated. Inorder to vary the distance between the piston heads, and consequentlythe maximum capacity of the chambers alternately opened on each side ofthe partition, one piston, as the piston 185, is mounted upon a-sleeve197 abutting against an adjusting nut 198 arranged to engage the reducedthreaded end 199 of the piston stem. This rod is suitably calibrated toindicate the volume of oil discharged at 7 each stroke of the piston, ashereinafter explained. On both sides of the partition, ad-

jacent the partition, the cylinder is formed with ports, marked 187 and188 which are in free communication, respectively, with branch passages141*.and 141 between the heated oil inlet pipe 141 and a discharge pipe191 leading to a spray pipe 143 arranged at the topof the pug mill.Communication between the pipe 141 and either the branch passage 141 orthe branch passage 141 is governed by a three-way valve 189, which maybe ordinary construction, not illustrated,

and communication between the discharge pipe 191 and either one of thebranch pipes 141 or 141 is governed by a similar threeway valve 190arranged to be shifted simultaneously with the valve 189. Thearrangement is such that in one position of the valves the port 187 willbe in communication through the valve 189 with the inlet pipe 141 whilethe branch passage 141* is shut off from the discharge pipe 191 by thevalve 190 and at the same time communication between the inlet pipe 141and branch passage 141 will be'closed by the valve 189 while the port188 will be in communication through the valve 190 with the dischargepipe 191. In the opposite position of the two valves the communicationswill be reversed, that is, the oil will be free to enter the oppositecham-' ber of the cylinder through the branch pipe 141 and port 188 andthe oil which hacl entered through the port 187 into the other cylinderchamber is free to return and pass through the branch passage 141 to thedis-

